Here's Kraftwerks Dyno's for a reference point. Both Dyno's were performed on a Rototest HUBDYNO.
C30 Blower
This one is Stock BRZ vs Supercharged BRZ (95mm pulley) with stock headers and exhaust running 91 octane fuel. This shows a gain of 81.9HP and 55.1TQ.
This one is Stock BRZ vs. Supercharged BRZ (95mm pulley) with the forthcoming Skunk2 Headers and Exhaust and fueled with E85. I've been told that the headers are going to be part of their Alpha Series line and should be released in January. This shows a gain of 127.1HP and 83.2TQ.
This one is Stock BRZ vs. Supercharged BRZ (90mm pulley) with the forthcoming Skunk2 Headers and Exhaust and fueled with E85. This shows a gain of 180.8HP and 119.4TQ.
C38 Blower
Here are results using a C38 on an Automatic.
This dyno sheet shows 91 octane numbers at 262.7HP and 204.6TQ. This is an increase of 108.3HP and 70.7TQ.
This dyno sheet shows E85 numbers at 341.5HP and 244.5TQ. This is an increase of 187.1HP and 110.6TQ
Engine bay layout. Oil cooler sandwich plate that is shown is a Skunk2 product. The oil cooler is anticipated to be released in time to ship with the Supercharger kit, sold separately though.